题干

家庭用的电热饮水机,有加热和保温两种工作状态.加热前温控开关S1处于闭合状态,闭合开关S后饮水机开始加热,当水箱内水温达到98℃时温控开关S1自动断开,饮水机处于保温状态;当水温降至一定温度t时,S1又闭合重新加热.饮水机的铭牌数据与电路原理图如下:

水箱容量

额定电压

加热功率

保温功率

2L

220V

440W

40W

求:

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     When Regina Spektor moved to the Bronx from Russia as a young child of 9, she could speak no English and her family was so poor that they could afford nothing. Yet she carried with her a love of the piano and music.

     "For me, the thing that I loved the most was playing the piano, so when we left Russia I was so afraid I would forget how to play and I would just find a little table and play my pieces," she told "When you spend your life doing something like playing the piano and then you take that away, it's so surreal."(离奇的)

     Her father, Ilya Spektor, said that, little by little, the family saved enough money to afford their first apartment.

     "I was a photographer and, in six weeks, I found my first job in a big photo lab in Manhattan," he said. On the subway one day, Ilya Spektor spotted a man carrying a violin case. The man also seemed to have an Eastern European accent. A conversation led to a visit and, eventually, Regina Spektor was introduced to Sonia Vargas, a piano teacher. She was a well-known professor who taught piano, took Spektor under her wing and trained her for years, at no cost. "I remember talking to Sonia," Spektor said. "She said that when a student is ready, a teacher appears. So she said that I must have been ready to study piano, and so that's why she came into my life."

     "Immediately, how she played," Vargas said. "You can tell the sound. The sound tell you whether the person loves the instrument, loves the music."

     Much later, while playing her own music and selling a CD that she'd created, Regina Spektor caught the attention of a music producer. The rest is history, complete with concerts around the world and performance in front of the Obamas at the White House.

     Regina Spektor greatly appreciated her parents, piano teachers and friends for helping her become the musician she is. “I love the idea that if you’re walking toward the world, the world will take some steps towards you,” she said.